Inclosed-arc device



J. A. ORANGE.

INCLOSED ARC DEVICE.

APPLICATION FILED IvIAR. 6. ms.

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Inventor: John DI. Orange w r 4. M His flttorneg UNITED STATES PATENT JOHN ARTHUR omen, or .scnnnncrnmr, NEW YbRK, Assreivon To GENERAL ELECTRIC comm, A CORPORATION or NEW YORK.

' INGLOSED-LRC DEVICE.

To all whom it may concern Beit known that I, JOHN ARTHUR ORANGE, a subject of the King of Great Britain, residing at Schenectady, in the county 'of Schenectady, State of New York, have invented certain new anduseful Improvements in Inclosed-Arc Devices, of which the following is a specification.

The present invention relates to electric are devices comprising a sealed bulb, containing electrodes of tungsten, or other suit able refractory conducting material, and containing a gaseous medium at substantial pressure. It is the object of my invention to provide automatic means for starting the are without using high potential devices.

In accordance with my invention, I have provided within the container a starting means comprising a body of easily vaporizable conducting material, for example, mercury, and an electrically heated conductor contacting therewith, electrical connectionsbeing provided so that upon passage of current some of the mercury, or the like, will be evaporated until contact between the mercury and a contacting conductor is broken, thereby striking an are at the mercury surface, which in turn starts the main arc between the refractory electrodes.

In the accompanying drawings, Figure 1 shows one embodiment of my invention in an alternating current lamp; Fig. 2 illustrates a modification for direct current operv ation; Figs. 3 and 4 show how the devices may be connected in a lighting circuit; and Fig. 5 shows an arrangement for applying 'the full line voltage upon starting, which is automatically reduced when the arcis operating.

Referring to Fig. 1, the lamp here shown comprises an elongated envelop 1 having an intermediate constriction at 2, givingthe efi'ect of two chambers. The electrodes 3, 4 consist of tungsten, tantalum, or other suitable highly refractory material of low vapor pressure. The electrodes preferably are connected to stems 5, 6 of smaller cross-section than the leads 7, 8, which are sealed into the glass stem 32. For, example, with electrodes about 40 to 50 mils in diameter, the stems 5, 6 may have a diameter of about 10 mils, and the leads 7, 8 a diameter of about 30 to 40 mils. The electrodes may be separated a distance of about 30 to mils, depending on the operating characteristics desired. The

Specification of Letters Patent.

Patented June 10, 1919.

Application filed March 6, 1916. Serial m. 82,387.

bulb 1 contains a filling of inert gas, such, for example, as nitrogen or argon, preferably at a pressure of about one-third of an atmosphere.

Connected to the current supply, and conveniently attached to the electrode stems, are

conductors 9, 10, preferably coiled, and dipping into a pool of mercury 11. These conductors consist of refractory material, preferably tungsten, molybdenum, tantalum, or the like, and have a resistance adapting them to operate at a temperature high enough to rapidly evaporate mercury upon passage of current so as to break contact of one of the conductors with the mercury, and preferably the contact of both conductors, thereby striking an are or arcs. An are between the end of either of ,the conductors 9 or 10 travels up the conductors and starts an are between the main electrodes 3, 4. The

heat of the arc maintains the part of the- 'in Fig. 3, for alternating current lamps 17, 18, and in Fig. 4 for direct current lamps 19, 20 in aseries circuit 21. As the individual, lamps do not have identical starting charac-lteristics, and do not start at the same moment, a high voltage is impressed successively on the lamps as the contact with the mercury globule is broken and the circuit opened.

An arrangement for still more positively applying a starting voltage higher. than the operating voltage is shown in Fig. 5. The arc device 22 is connected by the conductors 23, 24, in series with the transformer primary coil 25 wound on a laminated core 26 common to the secondary coil 27. As the 4 transformer has a high -r'eactance this arrangement is adapted particularly for multiple circuit operation. In shunt with the terminals, of the-device'22 is'a coil 28 which is wound so that a relatively high voltage, say a hundred volts, is necessary to cause it to pick up its armature 29, but the arc-operating voltage, say 12 volts, is sufficient to cause it to hold its .armature. When, for example, the lamp is operated in a 110 volt circuit, and when sufficient mercury evaporates to break the circuit in the lamp, the magnet 28 is actuated, making contact at 30 with the conductor 23 and the free terminal of the secondary coil 27, the speed of response .of

the armature being adjusted by a dash-pot 31. The coil 27 furnishes a desired lower voltage current, say 12 volts, of correspondingly higher amperage, for operating the device. The arrangement just described is equally well adapted for series operation, but in that case the transformer should not be of high reactance. By the use of the mechanism shown in Fig. 5, it is practicable to operate, for example, a 20 ampere lamp on a 6 ampere series circuit.

What I claim as new, and desire to secure by Letters Patent of the United States, is 1. The combination of a container, elec trodes of refractory conducting material therein, a quantity of mercury, a refractory conductor connected at one terminal to one electric circuit through said conductor and body of mercury.

3. electric arc device comprising the comblnation' of a container, electrodes of tungsten-therein, a filling of gas inert with respect to said electrodes at high temperatures, a quantity of mercury, a refractory conductor connected at one end immediately adjacent to one of said electrodes and at the other end to the mercury,and a second electrical connection to themercury.

4. An electric arc device comprising the combination of an elongated container, electrodes of tungsten located near one end of said container, a filling of argon, a quantity of mercury adjacent said electrodes when the container is in the operating position, and filaments of tungsten connected, respectively, adjacent said electrodes and having free ends contacting with the mercury.

5. The combination of a sealed container, cooperating electrodes of refractory mate rial therein separated by a space, a quantity of easily vaporiz-able conducting material, and conductors completing within saideontainer an electrical circuit between said electrodes, said circuit including said conducting material, one of said conductors at least being adapted to be heated to a temperature high enough to rapidly evaporate said ma terial and open the circuit.

6. An electric arc lamp comprising the combination of a container, electrodes of refractory material therein, a quantity of mercury, a refractory conductor connected respectively at one end to each of said electrodes and contacting at the opposite end with said mercury, at least one of said conductors having a length and resistance adapted to evaporate sufiicient mercury upon passage of current to break contact with the mercury and strike an are.

In witness whereof I have hereunto set my hand this 28th day of February, 1916.

' JOHN ARTHUR ORANGE. 

